The effects of calcium and magnesium in hyperkalemic cardioplegic solutions on myocardial preservation.

Sustained left ventricular pressure development during each infusion of a cold calcium-containing hyperkalemic cardioplegic solution has been observed in rat hearts. The present study was undertaken to relate such contraction (i.e.

Myocardial preservation related to magnesium content of hyperkalemic cardioplegic solutions at 8 degrees C.

This study investigates whether the addition of magnesium to a hyperkalemic cardioplegic solution containing 0.1 mM ionized calcium improves myocardial preservation, and whether there is an optimal magnesium concentration in this solution. Isolated perfused rat hearts were arrested for two hours by this cardioplegic solution, which was fully oxygenated and infused at 8 degrees C every 15 minutes to simulate clinical conditions.

Tissue distribution of atrial natriuretic factor in normal and pathologic human hearts.

The tissue distribution and possible neuroendocrine nature of atrial natriuretic factor (ANF) were studied, using the avidin-biotin-peroxidase technique and antibodies to ANF, chromogranin (Ch), and neuron-specific enolase (NSE). Tissues examined included: Group 1, formalin-fixed and fresh frozen atrial tissue from adjacent areas of the hearts from two heart-lung-transplant patients; Group 2, the entire atria and sampling of other areas from formalin-fixed hearts of five gunshot wound or automobile accident victims; and Group 3, formalin-fixed right auricular tissue from 19 open-heart-surgery patients. In each case of Group 3, the ANF score, expressed as the product of the percentage of stained areas by the staining intensity, was correlated with age, weight, height, blood pressure, ejection fraction, and degree of coronary arterial stenosis.

Retinal leakage in retinal vein occlusion: reduction after hyperbaric oxygen.

A 54-year-old woman with a history of bilateral central retinal vein occlusion, probably due to an inflammatory process, developed a hemispheric retinal vein occlusion with cystoid macular edema in her only seeing eye. Five months later, in the absence of improvement in vision and macular edema, she received on two occasions a 2-weekly course of twice daily 100% hyperbaric oxygen. After each course retinal leakage, as assessed by vitreous fluorophotometry, decreased from abnormal to the normal range while visual acuity improved by two lines.

Lectin histochemistry of normal lung and pulmonary adenocarcinoma.

In order to evaluate the staining pattern of glycoconjugate profiles in adenocarcinomas of the lung, pulmonary adenocarcinomas were classified according to their: (a) degree of differentiation; (b) cellular subtyping and mucus secretion; and (c) immunohistochemical characteristics. Studies were performed on 42 pulmonary adenocarcinomas using eight lectins. Formalin-fixed, paraffin-embedded tissues were stained with avidin-biotin peroxidase complex methods.

Quadricuspid aortic valve and single coronary ostium.

We describe an autopsy patient in whom a rare congenital anomaly of quadricuspid semilunar aortic valve and coronary arteries originating from a single orifice of one aortic sinus occurred. To the best of our knowledge, this combination of cardiac anomalies has not been reported.

Differences in lectin binding of malignant pleural mesothelioma and adenocarcinoma of the lung.

In order to differentiate between malignant pleural mesothelioma and adenocarcinoma of the lung, the glycoconjugate profiles of 6 reactive mesothelial lesions, 23 mesotheliomas (17 epithelial, 1 desmoplastic, 2 biphasic, and 3 fibrous types), and 28 well-differentiated pulmonary adenocarcinomas were evaluated with the use of 8 lectins in addition to anti-carcinoembryonic, anti-keratin and anti-epithelial membrane antigen. Formalin-fixed, paraffin-embedded tissues were stained with the avidin-biotin peroxidase complex method. Reactions of wheat germ (WGA) and peanut (PNA) agglutinin with neuraminidase treatment lectins were positive in 5 of 6 (83%) and 3 of 6 (50%) cases, respectively, in reactive mesothelial lesions.

Targeting of cytotoxic cells against tumors with heterocrosslinked, bispecific antibodies.

Cytotoxic cells express specific receptors on their surfaces by which they distinguish altered or foreign cells from normal autologous cells. Recently, a method has been developed by which the natural recognition system of cytotoxic cells can be artificially manipulated, giving rise to cytotoxic cells of any desired specificity, including specificity against tumor and virally infected cells. The method for retargeting cytotoxic cells employs heterocrosslinked antibodies, in which one antibody is directed against the cytotoxic cell receptor (CCR) involved in lysis, while the second antibody is directed against a target cell structure, for example a tumor or viral antigen.

The heart after surgery for ischemic heart disease.

Morphological abnormalities related to the surgical treatment of ischemic heart disease are discussed. Catheterization, angioplasty, or intraarterial thrombolysis may lead to perforation, endothelial injury, thrombosis, or dissection of the artery; endothelial injury results in intimal thickening. Laser angioplasty produces a localized area of thermal and acoustic injury that may heal without luminal compromise.

Expression of Fc gamma receptors on splenic T cells of mice infected with Plasmodium chabaudi adami.

In previous studies, it was shown that mice infected with Plasmodium chabaudi adami have a deficiency in their production of IgG1 immunoglobulin, suggesting isotype-specific immunoregulation. In order to examine this phenomenon in further detail the expression of Fc gamma receptors (Fc gamma R) on T cells obtained from mice infected with P. chabaudi was studied by flow cytometry.

Human K/natural killer cells targeted with hetero-cross-linked antibodies specifically lyse tumor cells in vitro and prevent tumor growth in vivo.

We have induced fresh peripheral blood K/natural killer cells to lyse a variety of target cells by coating them with anti-Fc gamma receptor (anti-Fc gamma R) (CD16) antibody hetero-cross-linked with anti-target cell antibody. The cytotoxic cell mediating this activity is different, as judged by depletion studies, from the CD3+, CD8+ T cell which is targeted by anti-CD3 cross-linked to anti-target cell antibody. Targeted K cell activity from some donors is enhanced by exposure to interleukin 2 but not interferon-gamma; other donors exhibit high amounts of this activity without stimulation.

Calcium-induced ventricular contraction during cardioplegic arrest.

Cardiac arrest induced by hyperkalemic perfusion is generally considered to represent a state of complete electromechanical arrest. However, high-energy phosphate concentrations and ventricular function decrease with increasing cardioplegic calcium concentrations, possibly because of elevated resting muscle tone produced by calcium influx. We examined isolated rat hearts containing an isovolumic intraventricular balloon for the presence of contractile activity during the administration at 10 degrees C of a cardioplegic solution containing potassium, 20 mEq/L.

Oxygenation of cardioplegic solutions. Potential for the calcium paradox.

Oxygenation of crystalloid cardioplegic solutions is beneficial, yet bicarbonate-containing solutions equilibrated with 100% oxygen become highly alkaline as carbon dioxide is released. In the isolated perfused rat heart fitted with an intraventricular balloon, we recently observed a sustained contraction related to infusion of cardioplegic solution. In the same model, to record these contractions, we studied myocardial preservation by multidose bicarbonate-containing cardioplegic solutions in which first the calcium content and then the pH was varied.

Incessant ventricular tachycardia in infants: myocardial hamartomas and surgical cure.

Infants with incessant ventricular tachycardia (occurring greater than 10% of the day) have generally been described in pathologic studies. This report describes 21 patients with incessant ventricular tachycardia present greater than 90% of the day and night; the age at diagnosis ranged from birth to 30 months (mean 10.5 months).

Optimal myocardial preservation with an acalcemic crystalloid cardioplegic solution.

The effect of the calcium and oxygen contents of a hyperkalemic glucose-containing cardioplegic solution on myocardial preservation was examined in the isolated working rat heart. The cardioplegic solution was delivered at 4 degrees C every 15 minutes during 2 hours of arrest, maintaining a myocardial temperature of 8 degrees +/- 2 degrees C. Hearts were reperfused in the Langendorff mode for 15 minutes and then resumed the working mode for a further 30 minutes.

Human T cells targeted with anti-T3 cross-linked to antitumor antibody prevent tumor growth in nude mice.

Human peripheral blood T cells were tested for the ability to prevent tumor growth in nude mice when targeted with anti-T3 cross-linked to antitumor antibodies. LS174T human colon adenocarcinoma cells were mixed with human PBL coated either with anti-T3 (Fab) cross-linked to 315F6 (Fab) (an antitumor monoclonal antibody) or with no antibody, and were injected subcutaneously into nude mice. Tumor growth was totally inhibited at effector to target (E:T) ratios of 7.

Pathologic features of myocardial hamartomas causing childhood tachyarrhythmias.

We have observed in 11 infants, aged 2 years or less, a distinct clinicopathologic lesion responsible for tachyarrhythmias that were fatal in 96% (25/26) of previously reported cases. Nine of the 11 patients, who underwent electrophysiologic mapping and surgical excision of the lesion, have survived, with follow-up periods ranging from 1 month to 6 years. The morphologic findings in these 11 patients and in the 26 cases cited in the literature are reviewed.

Specific lysis of human tumor cells by T cells coated with anti-T3 cross-linked to anti-tumor antibody.

Heteroaggregates containing anti-T3 cross-linked to anti-target cell antibodies have been shown to cause human T cells to lyse target cells that express antigens recognized by the anti-target cell antibody. In this study, we test targeted human T cells for the ability to lyse human tumor cells as a first step toward the application of this phenomenon to tumor immunotherapy. Several monoclonal anti-human tumor antibodies were assayed for binding to a number of human tumor lines and for the ability to promote specific tumor cell lysis when cross-linked with anti-T3.

Time dependence of the oxygen cost of force development during systole in the canine left ventricle.

To determine whether the oxygen cost of force development in the canine left ventricle is constant throughout systole, we inserted fluid-filled Latex balloons into eight isolated canine left ventricles perfused via support dogs. Balloon volumes were varied by a hydraulic servoactuator designed to withdraw preset volumes rapidly (0.5 ml/msec) beginning at a specified ejection pressure.

Effect of preload on ischaemic and non-ischaemic left ventricular regional function.

The response to preload of ischaemic and non-ischaemic regions of the left ventricle was studied in 14 dogs undergoing right heart bypass with mean aortic pressure and heart rate held constant. Regional function was measured by sonomicrometry before and after coronary artery occlusion. In the ischaemic region, as expected, there was paradoxical systolic lengthening (that is, systolic shortening was negative) but as stroke volume was progressively increased end diastolic length increased, whereas end systolic length changed little; thus systolic lengthening decreased (systolic shortening increased).